Adventurers are Scientists who rely not only on their command of Science but their physical acumen, wits and daring to explore new parts of the world, fight "villains" and perform heroic deeds. While many would scoff at them as simplistic, the four-color inheritors of Doc Savage and John Carter do have a certain nostalgic appeal. Modern Adventurers take on a more pragmatic approach, using their fabulous Science to build fantastic (but often concealed) armor and weaponry with which to pursue their crusades against criminals, hypocrites and madmen. Again, they don't make up a real force within the Tradition (there's no "Legion of Super Heroes") so much as a new breed of Scientist.
Pages 70 - 71, Mage: The Ascension - Chapter Two: The Traditions